美蓝还原法快速测定结核分枝杆菌药物敏感性

Rapid detection of susceptibility of Mycobacterium tuberculosis to drugs by methylene blue reduction test

目的探讨美蓝还原法快速测定结核分枝杆菌(MTB)药物敏感性,以建立一种简单、快速、敏感和低成本的药敏方法。方法用美蓝还原法测定50株结核分枝杆菌抗结核药物的药敏性,并将结果与传统改良罗氏培养基的绝对浓度法的结果进行比较分析。结果美蓝还原法进行INH、RFP、EMB、SM、LVFX药敏试验的敏感性分别为88.2%、94.7%、90%、91.2%、85.7%;特异性分别为93.8%、93.5%、100%、93.8%、95.3%;准确性分别为90.0%、94.0%、94.0%、96.0%、94.0%。两种方法测得MIC的相同率分别为88.0%、94.0%、90.0%、96.0%、92.0%。结论通过与绝对浓度法比较,美蓝还原法快速测定结核分枝杆菌药物敏感性具有简单、快速、成本低廉且敏感性较高的优点,可以成为抗结核药物药敏试验方法之一。

Objective To develop a rapid method to detect drug susceptibility of Mycobacterium tuberculosis to drugs by methylene blue reduction test. Methods Fifty M.tuberculosis isolates were tested their susceptibilities by methylene blue reduction test and the results were compared to that of the absolute concentration method on Lowenstein-Jensen medium.Results The susceptibility of Mycobacterium tuberculosis to INH, RFP, EMB, SM, LVFX by methylene blue-reduction method were 88.2%,94.7%, 90.0%, 91.2% and 85.7%,respectively; with the specificities of 93.8%, 93.5%, 100.0%, 93.8%and 95.3%,respectively;and the accuracy as 90.0%, 94.0%, 94.0%, 96.0% and 94.0%,respectively. The consistency of MIC between the two method for the 5 drugs were 88.0%, 94.0%, 90.0%, 96.0% and 92.0%,respectively. Conclusion The results indicated that the methylene blue reduction method for susceptibility test of Mycobacterium tuberculosis to anti-M.tuberculosis drug was sensitive and specific with the advantages of simplicity, rapidness and low cost, which can be used for susceptibility tese of Mycobacterium tuberculosis to drugs.